1. Field
The following relates to data-enabled mobile transceiver devices, such as data-enabled mobile phones, digital assistants, and smartphones, and more particularly to using these devices for navigation based on received satellite signals, such as Global Positioning System (GPS) signals, and dead reckoning techniques, at times when GPS signals are unavailable.
2. Related Art
Portable communication devices, such as mobile phones, increasingly have GPS receivers built-in. The devices can use received GPS signals to determine a current position of the mobile device, and in turn use that current position information as input for navigation applications. GPS signals are not always reliably received by a mobile device, such that a mobile device cannot always obtain a positional fix when desired, such as when using a navigation application on the mobile device while driving an automobile. In particular, it is known that tall objects, such as buildings and trees obstruct GPS signal reception. However, it remains desirable to be able to continue to provide position information and navigation assistance even when the device cannot receive GPS signals adequate to determine a position of the device.